Reached max allowble probes

L1 Bithead

Reached max allowble probes

Users have no access.


[Debug  988]: Reached max allowble probes, adding IP to queue for later processing.  Probing 40 IPs, list contains 117 entries
Reached max allowble probes, adding IP to queue for later processing.  Probing 40 IPs, list contains 117 entries
Probing IP failed. For initial probing, try again after 3 min
[ Info  938]: IP is already in the probing queue

[Debug  484]: IP for acme\user cannot be probed.  List is full of 201 entries, currently probing 40


+0500 Error: pan_user_id_agent_proc_ipuser(pan_user_id_uia.c:444): pan_user_id_agent_send_ip_user_to_dp() failed for user acme\user

+0500 Error: pan_user_id_uia_handle_ip_msg_i(pan_user_id_uia_v5.c:141): pan_user_id_agent_proc_ipuser(vsys 1, ip, user acme\user, timestamp 1466142528) failed


What we can do?

Community Team Member

Re: Reached max allowble probes


Having debug on in a scaled deployment can sometimes cause problems.  You could try disabling or lower the debug level to alleviate the problem.


Alternatively you could disable probing :



Splitting the load over multiple agents is also a good idea in a scaled deployment.



L1 Bithead

Re: Reached max allowble probes


The problem because of NetBIOS probes have queue

When we disable NetBIOS probes all users have no access after relogon.


Than we enable WMI probes the problem of User-ID disapear

for correct user rights for WMI probes we use:   wmic /node:(IP address) computersystem
get username


The installation is about 1500 users and 2 User agents.

L4 Transporter

Re: Reached max allowble probes

First of all the user to IP mapping should be refreshed at user logon. Please make sure that every logon is generating security events on the LDAP servers and the the agent is able to map them,


Seems that almost all of your user to ip mapping relies on windows probes which is not ideal, As an alternative method you could enable kerberos SSO in captive portal.




L2 Linker

Re: Reached max allowble probes

Probing is more of an active user mapping to verify a user is still linked to a certain IP address. The LDAP server creates user-to-ip mappings where WMI probing actively verifies a user is still valid. The probing variable can be changed from the default setting to a longer duration so that clients are not probed as often or possibly disable probing altogether. When changing the duration, you may set the timer to half the value of your DHCP renewal timer


By Palo Alto technical support





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